Skin conditions or dermatological disorders afflict millions of people each day. These skin conditions may be acute (lasting for just a few minutes to a few hours) or chronic conditions that may plague an individual for days, months, years or even a lifetime. A multitude of different dermatological conditions exist and may be fungal, bacterial, or viral based, or may be a non-infective, immunological response such as an inflammatory response with or without an allergic component, or may be idiopathic. Accordingly, symptoms may vary and may range from mild itching, redness and swelling to severe pustules and open sores and even in certain instances may lead to debilitating manifestations such as disabling ulcerations. Regardless of the cause or particular symptoms, dermatological disorders may substantially affect the quality of an individual's life.
Topical dermatological agents have been employed for decades to treat or otherwise alleviate the symptoms of a variety of dermatological conditions. However, a number of these topical dermatological agents require a prolonged treatment regime of a particular dosage in order to be effective at treating a dermatological disorder. One problem that arises with the use of many of these topical dermatological agents is that they may require application over an extended period of time to be effective at treating a particular disorder, where such extended periods of time may be required due to the efficiency of the agent employed. Such extended treatment periods may be inconvenient and disruptive to a subject life.
The amount of time a particular topical dermatological agent may be used on an individual may be limited by side effects or potential side effects that may develop over such extended periods of time of use. The occurrence of side effects depends on the dose, type of topical dermatological agent and length of treatment and, of course, some side effects are more serious than others. While some side effects may be reversible, others are not and thus care must be taken to so that these types of side effects are avoided. Common side effects of some topical dermatological agents used to treat certain disease disorders include thinning of the skin, local burning, itching, irritation, dryness, redness of the skin, acne, striae or stretch marks, dilation of blood vessels in the skin, tachyphylaxis, skin color (pigmentation) changes, easy bruising, and the like.
For example, psoriasis affects approximately 2-3% of the world's population and about 7 million people in the U.S. Psoriasis is a chronic, inflammatory, hyperproliferative disease of the skin characterized by well-demarcated, erythematous, scaly plaques. Psoriasis may consist of one or two lesions or may be a widespread dermatosis with disabling arthritis or exfoliation. Although the exact pathogenesis of psoriasis remains undefined, there are several therapeutic options. For example, monoclonal antibodies have been employed in attempts to combat psoriasis, however this treatment option is used primarily to treat generalized psoriasis as opposed to localized psoriasis. Since most sufferers of psoriasis have only localized psoriasis, the mainstay of treatment remains the use of topical agents.
Topical steroids, such as triamcinolone, have been used in the treatment of psoriasis for years. While topical steroids are often effective in the treatment of psoriasis, their use may be associated with adverse side effects such as those described above as well as skin atrophy or systemic effects such as HPA-axis suppression if used extensively. Furthermore, tachyphylaxis may result from the use of the topical steroid. In clinical practice, while most localized lesions respond to topical corticosteroids, some lesions remain recalcitrant to even the strongest “Class I” topical steroids such as clobetasol. The use of Class I super potent topical steroids is typically limited to only two weeks because of potential side effects.
Accordingly, there remains a need to increase the effectiveness and/or efficiency of a dermatological agent, e.g., to shorten the otherwise extended treatment period (increase efficiency), increase the effectiveness of an agent, etc. A variety of protocols have been developed to try to increase the efficiency and/or effectiveness of a topical agent, although thus far such protocols have met with limited success. For example, dermatological agents have been provided in a variety of topical formulations such as creams, lotions, gels and the like in attempts to increase the delivery efficiency. However, while enabling direct, localized application of the dermatological agent to a skin surface, these topical formulations have not provided a complete solution as typically only partial improvement results even with an optimal formulation, e.g., oftentimes recalcitrant skin lesions remain, and/or treatment times have not been appreciably shortened.
Attempts to enhance the efficacy of the dermatological agent by covering these topical formulations with plastic wrap such as Saranwrap® once the formulations have been applied has also been tried and has met with some success in enhancing the efficacy of the dermatological agent. However, this method is messy, uncomfortable and inconvenient, for example the plastic wrap is difficult to keep in place, especially when positioned on an elbow, knee, shin, etc. In attempts to try to maintain the plastic wrap in position at an application site, adhesive tapes have been employed. However, many people have allergies to such adhesive tapes. Furthermore, a site may become irritated by the use of adhesive tape causing tape burns. Certain skin diseases such as psoriases tend to develop at the site of the superficial skin trauma caused by the tape.
Accordingly, there continues to be an interest in the development of new methods of topically administering a dermatological agent to a subject. Of particular interest is the development of such methods that are cost effective, easy to use, and which are effective as well as efficient at administering or enhancing the dermatological agent to the subject.
Relevant Literature
U.S. Patents of interest include: U.S. Pat. Nos. 5,120,544; 5,160,328; 5,270,358; 5,423,737; 5,476,443; 5,489,262; 5,501,661; 5,827,529; 6,039,940; 6,096,333; 6,214,374; 6,296,869; 6,348,212; 6,455,065. Also of interest are WO 02/078757 and WO 02/078756.